The present invention relates to a fuel valve for preventing over-fueling. In the fuel valve, when a fuel level inside a fuel tank reaches a predetermined level upon fueling, a ventilation path of a canister is blocked or partially blocked. As a result, an internal pressure of the fuel tank increases to raise a fuel level inside a fuel tube, so that a sensor at a fueling nozzle can detect the fuel tank is filled.
A conventional fuel valve includes a skirt support portion with an opening lower end disposed inside a fuel tank for covering around a connection portion between the fuel tank and a ventilation path of a canister. When a fluid level inside the fuel tank reaches the opening lower end of the skirt support portion, an internal pressure of the fuel tank increases. As a result, a fuel level inside a fuel tube rises so that a sensor at a fueling nozzle side can detect fill-up, thereby preventing over-fueling. (For example, as disclosed in Japanese Patent Publication (KOKAI) No. 10-500088)
However, since the fuel is quickly poured into the fuel tank through the fueling nozzle, the fuel surface inside the fuel tank sways or waves, resulting in being unstable. Therefore, in the skirt support portion described above, it is possible that the waving fuel surface touches the opening lower end of the skirt support portion. In that case, even if the tank is not filled-up yet, it is possible that the sensor at the fueling nozzle detects the fill-up.
Also, due to the rapid fueling, a large quantity of a gas inside the fuel tank passes through the ventilation path during the fueling. Thus, when the skirt support portion is used to detect the fill-up, the gas passing through the ventilation portion carries a part of the fuel into the canister side before the fuel level reaches the opening lower end of the skirt support portion, thereby damaging the canister.
An object of the present invention is to provide a fuel valve in which the sensor at the fueling nozzle can detect the fill-up accurately when the fuel tank is filled-up.
Another object of the invention is to provide a fuel valve in which a part of the fuel is prevented from entering the ventilation passage of the canister.
Further objects and advantages of the invention will be apparent from the following description of the invention.